1. Field of the Invention
The present invention relates to an electronic component having a printed conductor structure on a substrate.
2. Description of Related Art
Electronic components generally include a printed conductor structure on a substrate. Such electronic components may also have a thin film which contacts the printed conductor structure. The film generally has a smaller layer thickness than the printed conductor structure. Such electronic components are used, for example, as semiconductor-based gas-sensitive field effect transistors in sensor system applications. The film, which has a smaller layer thickness than the printed conductor structure, usually represents the gate electrode. Action by a gas to be detected generally results in a change in the current flowing through the transistor from the source electrode to the drain electrode.
To allow gas detection with the aid of semiconductors, surfaces are necessary which are permeable at least to individual constituents of the gas species to be detected. These may be components of a gas mixture as well as constituents of a gas molecule. Thus, for detecting ammonia, for example, gas-sensitive field effect transistors are used which are permeable to hydrogen, for example. The permeability is generally ensured by thin and/or porous layers. The thickness of these layers is generally in a range of 1 nm to 100 nm. In addition, in particular, the design of the porous layer as an electrically conductive film is advantageous, since this porous layer may then be used, for example, as a gate electrode of the semiconductor component.
However, it has been shown that in particular at high operating temperatures and in corrosive environments such thin, gas-sensitive layers frequently break down due to degradation. It has been shown that the degradation occurs primarily at the bridging of steps or edges and at the connection to thicker films. However, such steps or edges are present on the semiconductor components due to the successive deposition of various materials, and usually have a height in the range of 10 nm to 1 μm. The connection of the thin layer to a thicker film is usually used for electrically contacting the porous layer.
A gas-sensitive field effect transistor for detecting hydrocarbons is described in U.S. Pat. No. 5,698,771, for example.